In the reign of Charles I, the Church of England was sharply divided. The Church was backed by the King and led by the Archbishop of Canterbury, William Laud, earlier Rector of West Tilbury in Essex, who stood for ‘order and decency in the church’. In opposition were the Puritans, who included the famous preacher Stephen Marshall, Vicar of Finchingfield, as well as many other Essex clergy. When the Civil War broke out, most Puritans supported the Parliamentary side. After the Civil War, the Puritans were in control in every parish throughout the Commonwealth under Cromwell, the Lord Protector. Puritan churches were being established in which Presbyterian, Independent and Baptist ministers replaced the Anglican clergy. Theatres closed and even Christmas celebrations were denounced as Papist.

During Ray’s career at Cambridge, there was a climate of comparative religious tolerance. At the university it was customary for sermons to be preached by graduates not in holy orders, and Ray made many fine sermons, including The Wisdom of God in the Creation from which he created his great book in later life.

However, after a journey to the north of England, Ray returned to the University to find religious upheavals everywhere, colleagues ejected and his own position in question. Although disgusted by this situation and the ensuing intrigues, he decided to remain. This raised the question of an obligatory ordination to allow him to continue as a lecturer. At first, due to his dislike of ritual and his own Puritan sympathies, he decided against ordination. Later, he realised his life’s work was at the University and reluctantly accepted the invitation. He was ordained in London by the Bishop of Lincoln in 1660.

With the restoration of Charles II in the same year, the Anglican clergy were restored. Parliament then passed laws making it impossible for anyone to hold any office unless they took communion in the Anglican church and accepted the newly-revised Book of Common Prayer.

Two years later, the Act of Uniformity was passed by Parliament. Under this Act, all Fellows of the University were required to declare that those who had taken an oath under the ‘solemn league and covenant’ were not obliged to keep to that oath. Although Ray himself had not taken this oath, he was a man of principle and refused to say that an oath was not binding. As a result, he had to give up his Fellowship and his livelihood, and left Cambridge.

The University’s loss was the scientific world’s gain. Had he remained at Cambridge, he may never have become John Ray the Naturalist.